The proposed research is an investigation into basic processes responsible for normal visual perception. The research concerns the earliest perceptual processes-responsible for parsing the visual array. It focuses on perception which is independent of attention since it is this level of perceptual processing which must create the entities to which attention is subsequently directed. The research employs a new, but already validated, procedure designed to study perception under conditions of inattention. This procedure will be used to uncover the kinds of perceptual organization that are achieved and the features of stimulation which are perceived without attention, having already demonstrated that many features of visual stimulations which have been considered preattentive, in fact, require attention. The research also explores a new phenomenon, that of Inattentional Blindness which describes the fact that between 25 and 90% of subjects fail to see a stimulus to which they are not attending. It explores whether features of stimulation not reported under conditions of inattention are nevertheless processed. It aims to analyze what aspects of attention are responsible for the failure to perceive under conditions of inattention. Whether it is its spatial or resource aspect which is responsible. Whether it is the absence of the appropriate expectation or the presence of a distraction task.